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Cruise News: R/V David Johnson
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March 1999 |
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At Pier 39 in San Francisco, Hank Chezar tests the underwater camera system.
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In mid-January 1999, the R/V David Johnson returned to central San Francisco Bay for
follow-up studies of three bedrock knobs that rise above the unconsolidated sediment
to water depths of <39' (LLW). The rocks are within the general westbound traffic
zone and about 200 m from the Deep Water Traffic Lane, where oil tankers and cargo
vessels with drafts of 50'
routinely enter the bay; thus, a potential catastrophe
awaits. The rocks have been lowered by blasting in the past (late 1800s and early
1900s) and the Harbor Safety committee is meeting frequently to determine how to
tackle this problem under present rules and regulations.
At their invitation, John
Chin and Paul Carlson have attended several of the meetings. We (Mike Boyle, Paul
Carlson, John Chin, and boat skipper Gordon Smith) ran very successful high-resolution
seismic lines and a few sidescan sonar lines across the rocks and over some of the
sand shoal areas. Hank Chezar joined us for one day and we obtained some good video
over two of the rocks and over one of the sand shoals. Fortunately, we had our
camera deployment before the rains came to muddy up the water.
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March 1999
in this issue:
Lake Titicaca
Massachusetts Bay
R/V David Johnson
Black History Month
VIPS Project
Sea Education
cover story:
NRC at St. Pete
Coral Reefs
Boston Harbor Clean-Up
New England Fishery Management
Woods Hole Visitors
Menlo Park Events
March Publications List
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U. S. Department of the Interior | U.S. Geological Survey
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